1. Field of the Invention
The present invention relates to a combustion-operated setting including a combustion chamber, a ventilator located in the combustion chamber, and a motor for driving the ventilator and received in a receptacle of a motor supporting member and supported, at least at one of its axial ends, by an annular damping element.
2. Description of the Prior Art
Setting tools of the type mentioned above can be operated, e.g., with gaseous or vaporizable liquid fuels. In combustion-operated setting tools, a setting piston is driven by expanding combustion gases in the setting process. Fastening elements can then be driven into a substrate by means of this setting piston. Prior to a combustion process, the fuel is mixed with the air located in the combustion chamber by a fan or ventilator which is located in the combustion chamber. The fan is driven by a motor, preferably an electric motor. The forces occurring during a setting process lead to high accelerations of the setting tool. Also, large accelerations occur in cases of improper use when the energy of the setting piston must be absorbed entirely by the setting tool. These accelerations have a negative impact on the life of the fan motor.
A combustion-operated setting tool of the generic type with a combustion chamber and a ventilator arranged in the combustion chamber is disclosed in International Publication WO 2006/106866. The ventilator can be driven by a motor which is arranged in a receptacle in a rear wall of the combustion chamber. Annular damping elements which damp movements of the motor along its longitudinal axis are arranged between the two axial ends of the motor and the respective wall portions of the receptacle which are located opposite from the motor.
While it is true that the damping elements known from WO 2006/106866 damp occurring peak loads, it takes a relatively long time before the damping system is again at rest once it has been excited and set in oscillation. This kind of after-oscillation of the motor damping system means an increased alternating load for the motor, which shortens its life.